int main()
{
	int n;
	int num, pc;
	int a;
	int arr[3] = { 0 };
	scanf("%d", &n);
	for (int i = 0; i < 3; i++)
	{
		scanf("%d %d", &num, &pc);
		int a = ceil(n * 1.0 / num);
		arr[i] = a * pc;
	}
	int min = arr[0];
	for (int i = 0; i < 3; i++)
	{
		if (min > arr[i]);
		{
			min = arr[i];
		}
	}
	printf("%d", min);

	return 0;
}